The present invention relates to a high speed rotatable chuck for machine tools, which provides extremely high chucking or clamping pressures, permitting simultaneous machining of opposite ends or portions of elongated work, such as bar stock, tubular materials and the like.
Machine tool chucks provided with a hollow work holding element, having capacity to contract diametrically to work clamping condition and to expand diametrically to work releasing condition, are well known. It also is known to provide chucks having tubular work holding elements about which are mounted annular actuators, which may be advanced by a piston or piston-like means, and retracted by opposing releasing means, such as one or more springs. Examples of such chucks are disclosed in U.S. Pat. Nos. 3,072,416, 3,278,193, 3,533,636 and 3,731,942. Such devices, however, do not provide for high speed, high pressure "chucking" of elongated work stock, permitting the simultaneous machining of such work at opposite ends, or spaced portions thereof.